Biologia 72/12: 1529—1532, 2017 Section Zoology DOI: 10.1515/biolog-2017-0159 ‘ Short Communication Cambarellus patzcuarensis in Hungary: The first dwarf crayfish established outside of North America András Weiperth 1 , Blanka Gál 1,2 , Pavlína Kuříková 3 , Martin Bláha 4 , Antonín Kouba 4 & Jiří Patoka 3 1 Centre for Ecological Research, Hungarian Academy of Sciences, Danube Research Institute, Karolina út 29, H-1113 Budapest, Hungary; e-mail: weiperth.andras@okologia.mta.hu 2 Doctoral School of Environmental Sciences, E¨otv¨ os Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary 3 Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Department of Zoology and Fisheries, Kamýcká 129, CZ-16500 Prague-Suchdol, Czech Republic 4 University of South Bohemia in České Budˇ ejovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zátiší 728/II, CZ-38925 Vodňany, Czech Republic Abstract: In 2017, a new non-indigenous crayfish species was found established in Europe. The captured individuals were identified as an orange morph of the Mexican dwarf crayfish Cambarellus patzcuarensis Villalobos, 1943. Fifteen adults (including three ovigerous females) and 26 juveniles were collected in a thermal pond in Budapest, Hungary. Two additional adults were caught below the pond’s outflow in the adjacent Danube River. To our knowledge, this is the first record of a C. patzcuarensis population outside North America, which is also true for the rest of dwarf crayfish (family Cambaridae, subfamily Cambarellinae). With this finding, indigenous crayfish species in Europe are now more than two-fold outnumbered by non-indigenous species. An analysis of the probability of establishment of C. patzcuarensis in continental Europe revealed that specific regions in the south of the continent are suitable areas for the establishment of the species. Moreover, as a confirmed carrier of the crayfish plague pathogen, this species should be treated with caution and eradicated if possible. Key words: biological invasion; climate match; thermal water; dwarf crayfish Introduction The international trade in live ornamental animals is a well-known source of indigenous species worldwide (Padilla & Williams 2004). Contrary to commercial aquaculture where only a limited number of stakehold- ers possess large quantities of animals, the pet trade is characterised by limited numbers of exotic species kept by many hobbyists and accordingly higher risk of release in multiple locations. This trend was recently debated in relation to crayfish (Chucholl 2013; Faulkes 2015a). Around 30 crayfish species are available on the market in countries with long history of trade in aquatic animals for the pet industry, such as the USA (Faulkes 2015b), Germany (Chucholl & Wendler 2017), and the Czech Republic (Patoka et al. 2015); certain species have also been detected as trade animals in Greece (Pa- pavlasopoulou et al. 2014), Hungary (Weiperth et al. 2018), Kazakhstan (Uderbayev et al. 2017), the Russian Federation (Vodovsky et al. 2017), Slovakia (Lipták & Vitázková 2015), Turkey (Turkmen & Karadal 2012), and Ukraine (Kotovska et al. 2016). It is obvious that the propagule pressure of species under trade has in- creased. Moreover, crayfish are kept not only in indoor aquaria but also in garden ponds (Patoka et al. 2014b, 2017), and in outdoor tanks and ponds close to the restaurant which advertise crayfish as a delicacy (Chu- choll & Daudey 2008; Perdikaris et al. 2017). It is not surprising that released or escaped crayfish have been consequently recorded in many countries. The major- ity of crayfish species under trade belong to the North- American cambarids which often established in the wild (e.g., Chucholl & Daudey 2008; Novitsky & Son 2016; Patoka et al. 2016a). Material and methods During two field surveys in Budapest, Hungary (May 19 and 30, 2017), crayfish were collected using nine (5+4) plastic bottle traps baited with halibut pellets and cyprinid fish meat and left in the pond for 24 hours. Captured individuals were preserved for later identifi- cation in pure (96%) ethanol, and a single walking leg from four adult individuals was collected for genetic analysis. The initial morphological species identification was confirmed c 2017 Institute of Zoology, Slovak Academy of Sciences Brought to you by | Göteborg University - University of Gothenburg Authenticated Download Date | 1/24/18 7:11 AM